Ventilator shutter



Aug. 8, 1944. M, BI D 2,355,412

VENTILATOR SHUTTER Filed Feb. 18, 1943 2 Sheets-Sheet 1 1527MB? -M 51.227

H. M BIRD 2,355,412

VENTILATOR SHUTTER Filed Feb. 18, 1943 ZSheets-Sheet 2 1527mm M 5.44 17Patented Aug.

2,358,412 .vmmrn'roa sno'r'rna Homer-QM. Bird, Mlilmee, Ohio ApplicationFebruary 1:,1943, Serial Net-16,288 s (01. 93-119 This invention relatesto shutters' for use connection with the ventilating of buildings, and.

particularly to those of the type whichclose by gravity action and openunder air pressure from one side.

An object of the invention is the provision in a shutter of thischaracter, of simple and efficient means forautomaticallycounterbalancing with the exception of the lower one, laps the upperedge of the next successive blade, so that the blades may cooperate tocompletely close the frame opening. If more than one blade is used, asillustrated in the present case, they are connected and caused tooperate in unison by a bar 8 disposed at the draft side of the bladesand pivoted to an arm 9 projecting from each blade near the weight ofthe shutter blade or blades during an opening action, so as to maintainthe closing tendency of the blades under gravity action substantiallyuniform during a full opening movement thereof. a v

A further object of the invention is theprovision, in connection with-agravity closing shut-P ter, of simple and efliclent means which isadjustable tb determine the air pressure required for an initial openingof the shutter and which is also operable to automatically increase thecounterbalancing action of the shutter blade or blades substantially inproportion to an increasing tendency thereof to close as they are openedand approach a horizontal position.

The invention is fully described in the follow ing specification, and apreferred embodiment thereof illustrated in the accompanying drawings,in which Figure 1 is a face view of the draft side of a ventilatorembodying the invention, with the blades in closed position; Fig. 2 isacross-section on the line 2-2 in Fig. 1; Fig. 3 is an enlargedfragmentary vertical section of the ventiits top edge, and'in-thepresent instancecen trally of its ends.- These arms lpreferably angleupwardly, as shown, so that the point of connection of the bar with-eacharm is above the horizontal plane of the respective pivot when theblade-is in its pendent or substantially vertical closed position. I

The upper blade 3 of a set, or the single blade of a ventilator, if onlyone is used, has its pivot 4 spaced from the top of the frame opening 2,

lator on the line 3-3 in Fig. 1; Fig. 4 is a simi I lar section with theblades in partially open position, and Fig. 5 is a perspectivefragmentary enlargement of the counterbalancing means embodying theinvention, with the blade in closed position.

Referring to the drawings, I designates a ventilator frame for settinginto a building structure and forming a ventilating opening 2 in whichone or more shutter blades 3 are pivotally mounted in a manner to closeby gravity action and to open by air pressure thereagainst at one side.

The pivot rods 4 for the blades are horizontally disposed and mounted attheir ends in respective side bars 5 set into the frame i and secured toits side members, as shown in Fig. 2, or in any other suitable manner.The free inner side edges of the bars 5 are turned inward relative tothe frame opening to form flanges 6 which 'lap the blade ends at thedraft side thereof when the blades are in closed position. j

The pivot rods 4 are suitably spaced one above the other and each bladefrom the top down,

and such space, when the bladeis in closed position, is closed by a topextension III on the blade. This extension, in the present instance,extends forward relative to the direction of draft movement at or.immediately above the pivot bar 4,

jthence upward and then rearward, preferably on an upward incline, tothe plane of the blade body 3, thus formingthe blade above its pivotwith a rearwardly opening housing having the top portion I i. The topedge of this extension is formed with a forwardly turned lip 12, which,when the blade is in closed position, coacts with the complementalinturned edge of the top cross-bar IS in the frame I to form a closejoint.

A pendulum weight I5 is swingingly suspended within the housing from itstop portion II, with its center of gravity, when the blade is in closedposit on, positioned slightly forward of a vert cal plane common to theswinging axis of the blade,

whereby the weight acting through the extension.

l0 tends to hold the blades in closed position. The extent of suchclosing pressure is determined by an inward or outward adjustment of theweight p vot. and it is preferable to have such adjustment on anincline, so that as the weight pivot is moved outward from the verticalplane of the blade axis it approaches the horizontal plan of such axis.For the purpose of this adjustment, the top H of the blade extension ismade-0n an incline and the weight is suspended from a pivot plate Itthat is held to the under side of said top by a screw l1 passing througha slot lltherein, suchslot being transverse to the blade and weightaxes.-

The purpose of the extension l0 and pendulum weight I5 is to partiallybut not entirely counterto automatically increase the counterbalancingforce to compensate for the increase oi. the closing force which takesplace as the blade or blades,

continue to swing toward a horizontal or full open position. This actionis accomplished due to the weight I5 swinging rearward from the bladeextension as the blades open, thereby increasing the counterbalancingaction substantially the same extent as the closing force of the bladesincreases as they move toward full open position, and vice versa.

This provides a very sensitive acting ventilator and one, that opens avery considerable extent even under a light draft force and which isalso adjustable to'vary the initial opening force required.

I wish it understood that my invention is not limited to any specificconstruction, arrangement or form of the parts, as it is capable ofnumerou modifications and changes without departing from the spirit ofthe claims.

Having thus described my invention, what I claim as new and desire tosecure by United States Letters Patent is:

1. In a ventilator having a. vertically swinging blade normally standingat closed position and which swings from closed pendent toward ahorizontal position when opening, an extension on the blade above itsswinging axis, and means swingingly carried by said extension andautomatically acting to progressively increase the counterbalancingaction of said extension on the blade as it swings from closed towardfull open position so that its resistance against opening remainssubstantially constant for any position of the blade.

2. In a ventilator having a vertically swinging blade normally standingat closed position and which swings from closed pendent position towarda horizontal position when opening, an extension on the blade above itsswinging axis cooperating with the blade to close an opening in whichdisposed, and weight means swingingly carried by said extension abovethe swinging axis of the blade and automatically acting by its swingingaction relative to the blade to p g ess v y increase thecounterbalancing action of said extension on the blade as it swings fromclosed toward full open position so that its resistance against openingremains substantially constant for any position of the blade, said meanshaving its center of gravity in advance of a vertical plane common tothe blade axis when the blad is in closed position.

3. In a ventilator of the class described, a ventilator blade mountedfor vertical swinging movements and normally standing in closed pendentposition and opening under air pressure from one side, an extension onthe upper edge portion of the blade above its swinging axis, and apendulum weight swingingly carried by said extension and cooperatingtherewith to counterbalance the blade a predetermined extent and actingby it swinging action relative to the extension to progressivelyincrease its counterbalancing force as the blade swings upward fromclosed toward horizontal position.

4. In a ventilator of the class described, a ventilator blade pivotedfor vertical swinging movements and movable by gravity to pendent closedposition and opening by fluid draft pressure against one side thereof,an extension on the blade above its swinging axis, and a pendulum weightswingingly carried by said extension and disposed forward in thedirection 0! draft movement from .a vertical plane common to the bladeaxis to tend to resist a predetermined extent an initial opening of theblade, said weight swinging relative to the extension during an openingmovement of the blade and thereby acting to progressively in crease theblade counterbalancing force in correspondence with the increase of theclosing force on the blade as it swings from closed toward a horizontalposition.

5. In a ventilator. of the class described, a ventilator blade pivotedfor vertical swinging movements and movable by gravity to pendent closedposition, said blade having an extension above its pivot in the form ofa forwardly projecting rearwardly opening housing which cooperates withthe blade to close a ventilating opening in which disposed, and apendulum weight suspended within said housing extension from the topportion thereof and swinging rearwardly relative thereto during openingmovement of the blade, said weight and extension having their center ofgravity in advance of a vertical plane common to the axis of the bladepivot when the blade is in closed position and operating toprogressively increase the counterbalancing force on the blade as itswings from closed toward horizontal position in substantial accordancewith th increase of the closing force of the blade as it moves towardsuch position.

6. In a ventilator of the class described, a frame forming a ventilatingopening, a plurality of shutter blades mounted in said opening forvertical swinging movements with their swinging axes disposed in spacedrelation one above another in substantially a vertical plane whereby theblades are adapted to cooperate to close the opening, means connectingthe blades to cause them to have opening and closin movements in unison,an extension on the upper blade above its swinging axis cooperating withthe blades to close said opening, a pendulum weight; swingingly carriedby said extension above the axis of such blade and acting to impart apredetermined closing force to the blades when in closed position andalso acting during a movement of the blades from closed towardhorizontal position to progressively increase the counterbalancing forceon the blades as they swing from closed toward horizontal position insubstantial accordance with the increase of th closing force of theblades as they move toward such position. e

HOMER M. BIRD.

